Polymerization processes in the presence of catalyst compositions comprising (1) reaction product of a vanadium oxide and organic phosphorus compounds,(2) a hydrocarbyl silane and a halo-aluminum compound

ABSTRACT

DISCLOSED HEREIN IS A CATALYST COMPOSITION, A METHOD FOR MAKING IT, AND A METHOD OF POLYMERIZATION OF UNSATURATED COMPOUNDS; THE CATALYST COMPOSITION CONTAINS A PRIMARY COMPONENT (PRODUCED BY THE REACTION OF A VANADIUM OXIDE WITH AN ORGANIC PHOSPHORUS OXY COMPOUND) WHICH IS EMPLOYED IN CONJUNCTION WITH AN ORGANO-ALUMINUM COMPOUND AS A COCATALYST.

United States Patent POLYMERIZATION PROCESSES IN THE PRESENCE OFCATALYST COMPOSITIONS COMPRISING (1) REACTION PRODUCT OF A VANADIUMOXIDE AND ORGANIC PHOSPHORUS COMPOUND, (2) A HYDROCARBYL SILANE AND AHALO-ALUMI- NUM COMPOUND John W. Bayer, Perrysburg, and Donald W. Gagnonand William C. Grinonneau, Toledo, Ohio, assignors to Owens-Illinois,Inc.

No Drawing. Continuation-impart 0f apphcatlon Ser. No. 465,210, June 18,1965. This application Aug. 6, 1968, Ser. No. 750,492

Int. Cl. C08f 3/04, 3/30, 3/76 U.S. Cl. 26088.7 10 Claims ABSTRACT OFTHE DISCLOSURE Disclosed herein is a catalyst composition, a method formaking it, and a method of polymerization of unsaturated compounds; thecatalyst composition contains a primary component (produced by thereaction of a vanadium oxide with an organic phosphorus oxy compound)which is employed in conjunction with an or gano-aluminum compound as acocatalyst.

This application is a continuation-in-part of our Ser. No. 465,210 filedJune 18, 1965, and now U.S. Patent No. 3,427,257.

This invention relates to a process for the polymerization ofunsaturated compounds. Likewise, the invention is concerned with acatalytic composition of matter and a process for the preparation of thesame.

Polymerization processes and catalytic compositions of matter are widelyused for the preparation of a diverse range of polymers. These polymericcompositions are widely used, for example in the packaging andconstruction fields. Specifically, this invention relates to a newprocess and catalyst system whereby desirable solid polymers can beeconomically produced.

An object of this invention is to produce a new polymerization process.Other objects of this invention include the development of a newpolymerization catalyst and a process for the preparation of saidcatalyst. More specifically, an object of this invention is an improvedprocess and catalyst system for the polymerization of monomericcompounds, such as ethylene, propylene, styrene, and vinyl chloride.

The polymerization processes and catalyst of this invention are adaptedfor the preparation of a wide range of polymers. Monomers useful in thepresent polymerization process include olefinically unsaturatedpolymerizable monomeric compounds, both hydrocarbons and hydrocarbonssubstituted with polar groups, especially monomers containing ofl-unsaturation.

This invention is applicable to the preparation of both homo-polymericand copolymeric composition, such as (1) vinyl resins formed by thepolymerization of vinyl halides or by the copolymerization of vinylhalides with unsaturated polymerizable compounds, e.g., vinyl esters,a,fi-unsaturated acids, cap-unsaturated esters, a,fi-unsaturatedketones, c p-unsaturated aldehydes and unsaturated hydrocarbons such asbutadienes and styrenes; (2) polya-olefins such as polyethylene,polypropylene, polybutylene, and polyisoprene, including copolymers ofpoly-aolefins; (3) polystyrene, including copolymers of styrene withmonomeric compounds such as acrylonitrile, and butadiene; (4) acrylicresins as exemplified by the polymers of methyl acrylate, acrylamide,methylol acrylamide, acrylonitrile, and copolymers of these withstyrene, vinyl pyridines, etc.; (5) neoprene; and (6) unice saturatedpolyesters. This list is not meant to be limiting or exhaustive butmerely to illustrate the wide range of polymeric materials which may beobtained by the present invention.

The process and catalyst of this invention are particularly suited tothe preparation of high quality polymers from monomers such as ethylene,propylene, styrene and vinyl chloride.

The primary catalyst of this invention are produced by the reaction of avanadium oxide of the formula -wherein n is an integer from 3 to 5,

with an organic phosphorus oxy compound of the formula wherein R R and Rare independently members such as hydrogen, hydroxyl, alkyl having fromone to eight carbon atoms, alkoxy having from one to eight carbon atomsand aryl, wherein at least one member is an organic group.

The primary catalyst system can be prepared by the reaction of about 1to about 6 parts by Weight of the vanadium oxide with from about 1 toabout 6 parts by weight of the organic phosphorus oxy compound. A morepreferred composition is produced by the reaction of from about 1 toabout 4 parts of the vanadium oxide with from about 1 to about 4 partsof the organic phosphorus oxy compound. A most preferred primarycatalytic composition is produced by the reaction of 1 part of vanadiumpentoxide with 4 parts of phenyl phosphonic acid.

The primary catalyst system of this invention is produced by thereaction of the vanadium oxide with the organic phosphorus oxy compound.Reaction temperatures are usually in the range from about 50 to 200 C.,with reaction times being from about one minute to about 24 hours.Usually the reactants are present in intimate contact in a liquifiedinert diluent such as an aromatic or aliphatic hydrocarbon. The diluentor solvent is usually present in an amount effective to slurry theproduct primary catalyst formed by the reaction. This product is a solidand is insoluble in hydrocarbons. Other inert diluents can be employed.In any event when a diluent is employed operating temperatures areusually from about to about 200 C. and the reaction is effected usuallyfor a period of from about 1 to 24 hours. When a diluent is employed ausually preferred range of operating reaction conditions is atemperature of from about 50 to C. for a period of time from about fiveto about 24 hours. The most preferred primary catalytic composition asdescribed above is produced by the reaction of 1 part vanadium pentoxidewith 4 parts of phenyl phosphonic acid in the presence of benzene at atemperature of 80 C. for 24 hours.

It is to be noted that the catalyst of this invention can be prepared bydirectly reacting the vanadium oxide with the organic phosphorus oxycompound in the absence of a solvent. When this reaction technique isused reaction conditions are a temperature range of from about to about200 C. for a period of time of from about 1 minute to about 1 hour.

The above described catalytic composition of matter is utilized inconjunction with a a cocatalyst which is represented by the formulawherein R is a member such as alkyl having from one to eight carbonatoms and aryl; R is a member such as alkyl having from one to eightcarbon atoms, aryl and halogen;

R is a member such as alkyl having from one to eight carbon atoms, aryland halogen.

The usual range of weight ratios of the catalyst compsitions forpolymerization of the present invention is in the range from 1:10 to :1of the primary catalyst to the cocatalyst. A more usual weight ratio ofthe primary catalyst component to the cocatalyst is from about 1:2 to2:1. With the diethylaluminum chloride cocatalyst, an especiallyeffective cocatalyst, about equal parts of the primary catalystcomponent and the c-ocatalyst are often used.

Polymerization reactions utilizing the catalyst systems of thisinvention are carried out by the introduction of monomeric material intoa recation vessel while maintaining said reaction vessel at atemperature in the range from about minus 70 C. to 200 C. more usuallyfrom about zero to about 100 C. and maintaining the pressure at fromabout atmospheric to about 2,000 p.s.i.g.

It is obvious to one skilled in the art that the optimum reactionconditions for any given monomeric compound depend on thecharacteristics of said monomeric compound. It is likewise obvious toone skilled in the art that a polymerization reaction utilizing theprocess and catalyst of this invention can be carried out on acontinuous basis, for instance, by continuously contacting monomericmaterial with a bed of the solid catalyst of this invention. Likewise,the process of this invention can be carried out on a batch basis bycharging an autoclave with a fixed amount of a catalyst, diluent and amonomeric material.

The polymerization reaction according to this invention is carried outin the presence of an inert diluent such as an aromatic and aliphatichydrocarbon. Sufiicient diluent is usually present to allow theformation of a workable slurry with the product polymer.

The following examples will illustrate the preparation of polymericcompositions by means of the subject invention. These examples are givenfor purposes of illustration and not for purposes of limiting thisinvention.

EXAMPLE I A- catalyst was prepared by the reaction of 8.4 grams of V 0with 37 grams of phenyl posphonic acid. The reaction was carried out ata temperature of 80 C., for a period of time of 20 hours at atmosphericpressure, in the presence of 200 grams of benzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor with .48 gram of diethylaluminum chloride. 210grams of n-heptane was likewise charged into the reactor. Ethylene wasthen introduced into the reactor at a constant pressure of 20 p.s.i.g.During the polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of 2 hours, 19 grams of polyethylene wasobtained. The melting point of the product polymer was 197202 C. asdetermined on a Kofler hot bench.

EXAMPLE II The preparation of a primary catalyst was carried out by thereaction of 45.5 grams of V 0 with 158 grams of phenyl phosphonic acid.This preparatory reaction was carried out at a temperature of 80 C., fora period of time of 48 hours, at atmospheric pressure, in the presenceof 200 grams of benzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor with 0.35 gram of ethylaluminum chloride, 210grams of n-heptane was likewise charged into the reactor. Ethylene wasthen introduced duced into the reactor at a constant pressure of 20p.s.i.g. During the polymerization sequence, the temperature of thereactor was maintained at 57 C. At the end of 2 hours 21.0 grams ofsolid polyethylene was obtained.

EXAMPLE III By the reaction of 9.1 grams of V 0 with 61 grams of dioctylsaid phosphate and 16.4 grams HCl, at a temperature of C., a primarycatalyst was prepared. The reaction was allowed to proceed for 20 hours,at atmospheric pressure, in the presence of 220 grams of benzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor with 0.49 gram of diethylaluminum dichloride. 210grams of n-heptane was likewise charged into the reactor. Eethylene wasthen introduced into the reactor at a constant pressure of 20 p.s.i.g.During the polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of 2 hours 4.0 grams of polyethylene wasobtained. The melting point of the product polymer was above 260 C.

EXAMPLE IV 45.4 grams of V 0 and 158 grams of phenyl phosphonic acid wasadded to a reactor which was held at a temperature of 80 C. The reactiontime was 48 hours, during which time, the reactor was held atatmospheric pressure. The reaction was carried out in the presence of200 grams of benzene.

0.1 gram of the above described catalyst was charged into apolymerization reactor with .48 gram of diethylaluminum chloride. 500grams of n-heptane was likewise charged into the reactor. Ethylene wasthen introduced into the reactor at a constant pressure of 700-800p.s.i.g. During the polymerization sequence, the temperature of thereactor was maintained at 57 C. At the end of 2 hours, 215 grams ofpolyethylene was obtained. The product polymer melted at C. and had adensity of 0.930. The melting point was determined by a Du Pont 900,Diiferential Thermal .Analyzer.

EXAMPLE V A primary polymerization catalyst was prepared by the reactionof 18.2 grams of V 0 with 64.4 grams of diethyl ethyl phosphonate and14.4 grams of Water in the presence of 220 grams of benzene. Thereaction was carried out at a temperature of 80 C. for a period of timeof 20 hours at atmospheric pressure.

0.5 gram of the above described catalyst was charged into apolymerization reactor with 0.48 gram of diethylaluminum chloride. 210grams of n-heptane was likewise charged into the reactor. Ethylene wasthen introduced into the reactor at a constant pressure of 20 p.s.i.g.During the polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of 2 hours 9.5 grams of polyethylene wasobtained. The product polymer had a melting point of -195 C.

EXAMPLE VI A catalyst was prepared by the reaction of 9.1 grams of V 0with 61 grams of octylacid phosphate at a temperature of 80 C. for aperiod of'time of 20 hours at atmospheric pressure. The reaction wascarried out in the presence of 200 grams of benzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor with 0.4 8 gram of diethylaluminum chloride. 210grams of n-heptane was likewise charged into the reactor. Ethylene wasthen introduced into the reactor at a constant pressure of 20 p.s.i.g.During the polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of 2 hours 2.7 grams of solidpolyethylene was obtained. The melting point of the product polymer wasl95200 C.

EXAMPLE VII The preparation of a primary catalyst was carried out by thereaction of 45.5 grams of V 0 with 15 8 grams of phenyl phosphonic acidat a temperature of 80 C. The

reaction was allowed to proceed for 48 hours at atmospheric pressure inthe presence of 200 grams of benzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor with .45 gram of trihexylaluminum. 210 grams ofn-heptane was likewise charged into the reactor. Ethylene was thenintroduced into the reactor at a constant pressure of 20 p.s.i.g. Duringthe polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of 2 hours an amount of the order of 1-5grams solid polyethylene was obtained.

EXAMPLE VIII A catalyst was prepared by the reaction of 45.5 grams of Vwith 158 grams of phenyl phosphonic acid at a temperature of 80 C. Thereaction was allowed to proceed for 48 hours at atmospheric pressure inthe presence of 200 grams of benzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor with .45 gram of triethylaluminum. 210 grams ofn-heptane was likewise charged into the reactor. Ethylene was thenintroduced into the reactor at a constant pressure of 2 0 p.s.i.g.During the polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of 2 hours 13.5 grams of solidpolyethylene was obtained.

EXAMPLE IX A catalyst was prepared by the reaction of 45.5 grams of V 0with 158 grams of phenyl phosphoric acid, in the presence of 200 gramsof benzene. The reaction was carried out at a temperature of 80 C. for aperiod of time of 48 hours, at atmospheric pressure.

0.5 gram of the above described catalyst was charged into apolymerization reactor with 0.48 gram of diethylaluminum chloride. 210'grams of n-heptane was likewise charged into the reactor. Ethylene wasthen introduced into the reactor at a constant pressure of 20 p.s.i.g.During the polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of 2 hours 69.8 grams of polyethylene wasobtained. The melting point of the product polymer was 128 C.

EXAMPLE X A catalyst was prepared by the reaction of 4.5 grams of V 0with 15.8 grams of phenyl phosphonic acid at a temperature of 160 C. fora period of time of hours, at atmospheric pressure.

0.5 gram of the above described catalyst was charged into apolymerization reactor with 0.48 gram of diethylaluminum chloride. 210grams of n-heptane was likewise charged into the reactor. Ethylene wasthen introduced into the reactor at a constant pressure of 20 p.s.i.g.During the polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of 2 hours 3.0 grams of solidpolyethylene was obtained.

EXAMPLE XI A polymerization catalyst was prepared by the reaction of 8.4grams of V 0 with 37 grams of phenyl phosphonic acid. This preparatoryreaction was carried out at a temperature of 80 C., for a period of timeof 20 hours, at atmospheric pressure, in the presence of 200' grams ofbenzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor with .48 gram of diethylaluminum chloride.Propylene was introduced into the reactor at a constant pressure of 20p.s.i.g. During the polymerization sequence, the temperature of thereactor was maintained at 57 C. The polymerization was carried out inthe pressure of 210 grams of n-heptane. At the end of 2 hours traceamounts of solid polypropylene were obtained.

EXAMPLE XII A primary catalyst was prepared by the reaction of 6 18.2grams of V 0 with 63.2 grams of phenyl phosphonic acid. The reaction wasperformed at a temperature of C., for a period of time of 20 hours, atatmospheric pressure, in the presence of 220' grams of benzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor with 0.48 gram of diethylaluminum chloride. gramsof benzene was likewise charged into the reactor. 22.6 grams styrene wasthen introduced into the reactor at atmospheric pressure. During thepolymerization sequence, the temperature of the reactor was maintainedat 60 C. At the end of 2 hours, 1.0 gram of solid polystyrene wasobtained.

EXAMPLE XIII 0.5 gram of a primary catalyst was charged into apolymerization reactor with 0.48 gram of diethylaluminum chloride. Theprimary catalyst was prepared by the reaction of 18.2 grams of V 0 with63.2 grams of phenyl phosphonic acid. The primary catalyst was preparedby reacting these components at a temperature of 80 C. for a period oftime of 20 hours, at atmospheric pressure, in the presence of 220 gramsof benzene.

110 grams of benzene was likewise charged into the polymerizationreactor. 16.2 grams acrylonitrile was then introduced into the reactorwhich was held at atmospheric pressure. During the polymerizationsequence, the temperature of the reactor was maintained at 60 C. At theend of 2 hours, 2.0 grams of solid polyacrylonitrile were obtained.

EXAMPLE XIV A catalyst was prepared by the reaction of 45 .5 grams of V0 with 158 grams of phenyl phosphonic acid at a temperaaure of 80 C. Thereaction was allowed to proceed for 48 hours at atmospheric pressure.200 grams of benzene was present.

0.5 gram of the above described catalyst was charged into apolymerization reactor with 0.48 gram of diethylaluminum chloride and2.0 ml. tetrahydrofuran. 210 grams of n-heptane was likewise chargedinto the reactor. Vinyl chloride was then introduced into the reactor ata constant pressure of 20 p.s.i.g. During the polymerization sequence,the temperature of the reactor was maintained at 57 C. At the end of 2hours, 1.0 gram of solid poly(vinyl chloride) was obtained.

, EXAMPLE XV A primary catalyst was prepared by the reaction of 18.2grams of V 0 with 63.2 grams of phenyl phosphonic acid. This reactionwas carried out at a temperature of 80 C. for a period of time of 20hours, at atmospheric pressure, in the presence of 220 grams of benzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor along with 0.48 gram of diethylaluminum chloride.110 grams of benzene was likewise present in the reactor. 2.6 grams ofdivinyl benzene was then introduced into the reactor which was held atatmospheric pressure. During the polymerization sequence, thetemperature of the reactor was maintained at 60 C. At the end of 2.0hours, 2.0 grams of poly(divinylbenzen) was obtained in solid form.

EXAMPLE XVI A primary catalyst was prepared by the reaction of 7.3 gramsof V 0 with 25.3 grams of phenyl phosphonic acid at a temperature of 80C. This preparatory reaction was allowed to proceed for 20 hours, atatmospheric pressure, in the presence of 194 grams of benzene.

0.5 gram of the above described catalyst was charted into apolymerization reactor with 0.48 gram of triethylaluminum. 210 grams ofheptane was likewise charged into the reactor. 1,3-butadiene was thenintroduced into the reactor at a constant pressure of 20 p.s.i.g. Duringthe polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of 2 hours, 3.0 grams of solidpolybutadiene was obtained.

EXAMPLE XVII A catalyst was prepared by the reaction of 18.2 grams of Vwith 15.8 grams of phenyl phosphonic acid at a temperature of 80 C. Thereaction was carried out for 20 hours, at atmospheric pressure, in thepresence of 200 grams of benzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor with 0.48 gram of diethylaluminum chloride. 210grams of n-heptane was likewise charged into the reactor. Ethylene wasthen introduced into the reactor at a constant pressure of 20' p.s.i.g.During the polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of two hours, 52.3 grams of solidpolyethylene was obtained. The melting point of the product polymer was207 C.

EXAMPLE XVIII A catalyst was prepared by the reaction of 7.3 grams of V0 with 25.3 grams of benzene phosphonic acid at a temperature of 80 C.for a period of time of 22 hours, at atmospheric pressure. The reactionwas carried out in the presence of 176 grams of benzene.

0.5 gram of the above described catalyst was charged into apolymerization reactor with 0.5 gram of triphenylaluminum. 210 grams ofn-heptane was likewise charged into the reactor. Ethylene was thenintroduced into the reactor at a constant pressure of 20 p.s.i.g. Duringthe polymerization sequence, the temperature of the reactor wasmaintained at 57 C. At the end of 2 hours, 0.8 gram of solidpolyethylene was obtained.

What is claimed is:

1. A process for the polymerization of an olefinically unsaturatedcompound to produce a solid polymer thereof which comprises contactingthe olefinic compound with a cathalytic amount of a catalyticcomposition comprising (I) from about 1 to about 5 parts of a primarycatalyst which is produced by the reaction at about 50 to 200 C. of fromabout 1 to about 6 parts of a vanadium oxide represented by the formulawherein n is an integer from 3 to 5,

with from about 1 to about 6 parts of an organic phosphorous compoundrepresented by the formula wherein R R and R are independently hydrogen,hy-

droxyl, alkyl having from one to eight carbon atoms, alkoxy having fromone to eight carbon atoms or aryl, wherein at least one member is anorganic group,

and (II) from about 1 to about parts of a cocatalyst represented by theformula wherein R is alkyl having from one to eight carbon atoms oraryl, R is alkyl having from one to eight carbon atoms, aryl or halogen;R is alkyl having from one to eight carbon atoms, aryl or halogen.

2. A process for the polymerization of an olefinically unsaturatedcompound to produce a solid polymer thereof which comprises contactingthe olefinic compound with a catalytic amount of a catalytic compositioncomprising (I) from about 1 to about 5 parts of a primary catalyst whichis produced by the reaction at about 50 8 to 200 C. of from about 1 toabout 6 parts of a vanadium oxide represented by the formula wherein nis an integer from 3 to 5',

with from about 1 to about 6 parts of an organic phosphorus compoundrepresented by the formula i 132-1 =0 Ra wherein R R and R areindependently hydrogen, hydroxyl, alkyl having from one to eight carbonatoms, alkoxy having from one to eight carbon atoms or aryl, wherein atleast one member is an organic group.

and (II) from about 1 to about 10 parts of a cocatalyst represented bythe formula R is alkyl having from one to eight carbon atoms, aryl orhalogen;

R is alkyl having from one to eight carbon atoms, aryl or halogen,

at a temperature of from about minus 70 to about 200 C., at a pressureof from about atmospheric to about 2,000 p.s.i.g.

3. A process according to claim 2 wherein saturated compound isethylene.

4. A process according to claim 2 wherein saturated compound is vinylchloride.

5. A process according to claim 2 wherein saturated compound ispropylene.

6. A process according to claim 2 wherein saturated compound isacrylonitrile.

7. A process according to claim 2 wherein saturated compound is styrene.

8. A process according to claim 2 wherein saturated compound is divinylbenzene.

9. A process according to claim 2 wherein saturated compound is1,3-butadiene.

10. The process for the polymerization of an olefinically unsaturatedcompound to produce a solid polymer thereof which comprises contactingsaid compound with a catalytic amount of a catalytic composition (I)comprising from about 1 to about 5 parts of a primary catalyst which isproduced by the reaction at about 50 to 200 C. in the presence of aninert diluent of from about 1 to about 6 parts of a vanadium oxiderepresented by the formula said unsaid unsaid unsaid unsaid unsaidunsaid unwherein rt is an integer from 3 to 5,

with from about 1 to about 6 parts of an organic phosphorus compoundrepresented by the formula wherein R R and R are independently hydrogen,hy-

droxyl, alkyl having from one to eight carbon atoms, alkoxy having fromone to eight carbon atoms or aryl, wherein at least one member is anorganic group,

and (H) from about 1 to about 10 parts of a cocatalyst represented bythe formula 9 wherein 3,166,517 1/1965 R is alk 1 havi from one to ei htcarbon atoms or 3,427,257 11/1969 y g 3,476,732 11/1969 R is alkylhaving from one to eight carbon atoms, aryl 3,488,334 1/1970 or halogen;R is alkyl having from one to eight carbon atoms, aryl HARRY WONG,

or halogen,

at a temperature of from about 0 to about 100 C., and in the presence ofan inert diluent.

10 R0 12.60-94.93 Bayer et a1. 2 6088.7 Bayer et a1. 260-85.5M Bayer eta1. 260-85.5M

Primary Examiner U.S. C1. X.R.

mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,57Dated April 97 Inventor(s) John W. Bayer Donald W. Gagnon, and WilliamC. Grir It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:

|' C0lumn 6, line 5?; In Example XV "2 .6 grams" should be --22.6grams-- Column 3, line 20, "recation" should be --reacci0n1-:

Signed and sealed this 13th day or July 1971.

(SEAL) Atteat:

EDJARD M.FIETCHER,JR WILLIAM E SGHUYLER JR. Attesting OfficerCommissioner of Patents

